/*
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 *
 * This software is open source.
 * See the bottom of this file for the licence.
 */

package com.googlecode.bluetools.dom4j.io;

import com.googlecode.bluetools.dom4j.Document;
import com.googlecode.bluetools.dom4j.Element;
import com.googlecode.bluetools.dom4j.ElementHandler;
import com.googlecode.bluetools.dom4j.ElementPath;

/**
 * This {@link com.googlecode.bluetools.dom4j.ElementHandler}is used to trigger {@link ElementModifier} objects in order to modify
 * (parts of) the Document on the fly.
 * 
 * <p>
 * When an element is completely parsed, a copy is handed to the associated (if any) {@link ElementModifier}that on his
 * turn returns the modified element that has to come in the tree.
 * </p>
 * 
 * @author Wonne Keysers (Realsoftware.be)
 */
class SAXModifyElementHandler implements ElementHandler {
	private ElementModifier elemModifier;

	private Element modifiedElement;

	public SAXModifyElementHandler(ElementModifier elemModifier) {
		this.elemModifier = elemModifier;
	}

	public void onStart(ElementPath elementPath) {
		this.modifiedElement = elementPath.getCurrent();
	}

	public void onEnd(ElementPath elementPath) {
		try {
			Element origElement = elementPath.getCurrent();
			Element currentParent = origElement.getParent();

			if (currentParent != null) {
				// Clone sets parent + document to null
				Element clonedElem = (Element) origElement.clone();

				// Ask for modified element
				modifiedElement = elemModifier.modifyElement(clonedElem);

				if (modifiedElement != null) {
					// Restore parent + document
					modifiedElement.setParent(origElement.getParent());
					modifiedElement.setDocument(origElement.getDocument());

					// Replace old with new element in parent
					int contentIndex = currentParent.indexOf(origElement);
					currentParent.content().set(contentIndex, modifiedElement);
				}

				// Remove the old element
				origElement.detach();
			}
			else {
				if (origElement.isRootElement()) {
					// Clone sets parent + document to null
					Element clonedElem = (Element) origElement.clone();

					// Ask for modified element
					modifiedElement = elemModifier.modifyElement(clonedElem);

					if (modifiedElement != null) {
						// Restore parent + document
						modifiedElement.setDocument(origElement.getDocument());

						// Replace old with new element in parent
						Document doc = origElement.getDocument();
						doc.setRootElement(modifiedElement);
					}

					// Remove the old element
					origElement.detach();
				}
			}

			// Put the new element on the ElementStack, it might get pruned by
			// the PruningDispatchHandler
			if (elementPath instanceof ElementStack) {
				ElementStack elementStack = ((ElementStack) elementPath);
				elementStack.popElement();
				elementStack.pushElement(modifiedElement);
			}
		}
		catch (Exception ex) {
			throw new SAXModifyException(ex);
		}
	}

	/**
	 * DOCUMENT ME!
	 * 
	 * @return Returns the modified Element.
	 */
	protected Element getModifiedElement() {
		return modifiedElement;
	}
}

/*
 * Redistribution and use of this software and associated documentation ("Software"), with or without modification, are
 * permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain copyright statements and notices. Redistributions must also contain a
 * copy of this document.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
 * following disclaimer in the documentation and/or other materials provided with the distribution.
 * 
 * 3. The name "DOM4J" must not be used to endorse or promote products derived from this Software without prior written
 * permission of MetaStuff, Ltd. For written permission, please contact dom4j-info@metastuff.com.
 * 
 * 4. Products derived from this Software may not be called "DOM4J" nor may "DOM4J" appear in their names without prior
 * written permission of MetaStuff, Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
 * 
 * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
 * 
 * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 */
